A biped walking robot as it is called in the art has so far been made able to walk with two legs by producing in advance data for a pre-established walking pattern (hereinafter referred to as “gait”) and actuating the legs in a controlled manner in accordance with the gait data so that the robot can bipedally walk as desired.
Such a conventional biped walking robot tends to become unstable in walking position due, for example, to floor or ground surface conditions and an error in the physical parameters of the robot itself and may then even turn over or fall violently.
However, while conventional biped walking humanoid robots are designed to fall as little as possible, they have never been designed so they when falling down take a safety way of falling down or then to scramble on their feet. To wit, no biped walking humanoid robot has been built having the capability of relieving shocks acting on its parts or the capability of detecting a particular state that it is falling. Further, if the conventional biped humanoid robot that fell down should be allowed to rise on its feet, the fact that the outer covering surface areas of its trunk body, legs and arms are desirably formed of relatively flat surfaces makes it hard to have the robot take successive actions dynamically and with smoothness for it to rise. This problem also applies if the conventional biped humanoid should be allowed to make a forward roll.
It is accordingly an object of the present invention to provide a biped walking humanoid robot having the capability of relieving shocks acting on its various parts when it falls violently and also the capability of detecting a particular state that it is falling.